1. Field
The present invention relates generally to a multicast apparatus and method and, more particularly, to a multicast apparatus and method, which guarantee reliability in a distributed network environment.
2. Description of Related Art
With progress in the realization of high-performance, small-size, and low-cost of information technology (IT) resources, IT resources such as computing, control, and communication resources have been rapidly configured as embedded resources in almost all traditional industrial areas, such as automobiles, shipbuilding, transportation, construction, power, and environment, as well as the embedded software (SW) areas of existing IT industry. In this way, industries and products having aspects completely different from those of existing industries and products based on the configuration of IT resources as embedded IT resources have appeared over all industrial areas. Since the number of objects corresponding to elements constituting the overall system has increased incomparably faster than the number of objects of existing networks, it is impossible to use a point-to-point communication method from the standpoint of an application.
Therefore, a one-to-many communication method for transmitting data to a specific number of objects desiring to receive data by using a multicast method which is one of a variety of efficient data transmission methods is required.
However, in order to actually apply a multicast service to in a large-scale distributed network environment, a problem may arise in that, even if the number of communication objects increases, reliability services must be provided.
This means that it is required to be able to detect a transmission failure and error occurring in a specific communication object and to recover such a failure and error in real time while large-scale communication objects are simultaneously transmitting/receiving data. However, as the number of communication objects, the number of data messages, the number of control messages required to detect errors, and the number of messages to be retransmitted for error recovery explosively increase in a network, it becomes more difficult to meet such requirements.
For example, there is technology disclosed in Korean Patent Application Publication No. 10-2010-0070361 entitled “Method and apparatus for performing adaptive forward error correction in response to combined automatic repetition requests for reliable multicast in wireless local area networks.” This patent describes only technology for forming a plurality of layers using Forward Error Correction (FEC) and Automatic Repeat Request (ARQ) in a multicast application requiring reliability, detecting the type of received packet, and selecting an error correction method corresponding to the received packet type.
In this way, in a large-scale distributed network environment, a new multicast method is required to actually apply a multicast service. In order to support such a multicast service, a mechanism must be provided which greatly reduces the number of messages by controlling a number of messages explosively increasing in the network in spite of an increase in the number of communication objects, and then detects a transmission failure and error in a specific communication object and recovers such a failure and error in real time.